Show HN: Mcptoon – MCP CLI client that cuts tool discovery tokens by 97%
The developer of 'mcptoon' introduces a CLI tool designed to reduce token consumption for Model Context Protocol (MCP) discovery by 97%. By replacing verbose JSON with a custom 'TOON' format, the tool aims to optimize context window usage for AI agents.
Why it matters
Token efficiency is a major bottleneck for AI development; tools that reduce overhead directly lower costs and improve performance for developers.
MCP tool discovery costs 10,000+ tokens. mcptoon costs 350.
One MCP client for every AI agent. Cross-platform. Zero dependencies.
If this saves you tokens, please star the repo — it helps others discover it.
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Every MCP-enabled conversation burns tokens on syntax, not data :
On a 128K context window, that's 30-55% gone . Not on work. On syntax.
mcptoon is a CLI client that connects to any MCP server (stdio or HTTP) and outputs TOON (Token-Optimized Object Notation) instead of JSON.
Zero dependencies. Pure Python. 50KB. Works with every AI agent — Claude Code, Codex, OpenCode, Cursor, CatPaw, anything that runs shell commands.
JSON (287 tokens) — what every other MCP client returns:
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